swenson



PATENTED FEB. 9, 1904.

G. T. SWBNSON.

BLEOTRICALLY PRODUCED SOUND INTENSIPIER.

APPLICATION FILED DEU.17, 1902.

2 SHEETS-SHEET 1.

N0 MODEL.

W/T/VE'ESES No. 751,818. PATENTED FEB. 9,1904. G. T. SWENSON. ELEOTRIOALLY PRODUCED SOUND INTBNSIFIER.

APPLICATION FILED DEC. 17, 1902.

NO MODEL. 2 SHEETS-SHEET 2.

Wives? v g 9 207 wifip. 32% m AVE/way:

UNITED STATES Patented February 9, 1904.

GUSTAF T. SIVENSON, OF SAN PEDRO, CALIFORNIA.

ELECTRlCALLY-PRODUCED-SOUND INTENSIFIER.

SPECIFICATION forming part of Letters Patent No. 751,818, dated February 9, 1904.

Application filed December 17, 1902. Serial No. 135,596. (No model.)

To all whom it may concern.-

Be it known that I, GUSTAF T. SWENSON, a citizen of the United States, residing near San Pedro, in the county of Los Angeles and State of California,have invented new and useful Improvements in Electrically-Produced-Sound Intensifiers, of which the following is a specification.

My invention relates to mechanism for intensifying or making louder an electrically produced or transmitted sound; and the primary object is to increase the effectiveness of a wireless-telegraph receiving system; and my mechanism is illustrated applied thereto; but it may be used in a telephone system.

In the accompanying drawings, forming a part hereof, Figure 1 is a diagrammatic representation of a wireless-telegraph receiving apparatus, partly in section and partly broken away. Fig. 2 is an enlarged fragmentary section of a part of one of the microphones.

Fig. 3 is a purely diagrammatic representation of a part of the circuits of Fig. 1 with the easing and magnets P and R omitted.

In the drawings, A is the aerial or mast wire of a wireless-telegraph station, which is connected to the ground B and also in shunt with my improved microphonic intensifier. This improved intensifier is composed of the oppositely disposed diaphragms C and D, which diaphragms are operated by the ordinary pole-receiving magnets P and R and are connected electrically by circuits S and T in multiple in shunt in the mast-circuit. These circuits have a common battery U. They are so placed magnetically that when vibrated by magnetic impulse they will move simultaneously in opposite directions. To the opposing faces of these diaphragms are affixed disks about one-half inch in diameter and three thirty-seconds of an inch thick. The disk E, which is affixed to and in electrical contact with diaphragm G, is of carbon and is provided in its face opposing the other disk with a plurality of small sockets E, which extend nearly through the disk. These sockets should be evenly spaced near the circumference of the disk. I have found in practice that twelve of these sockets produce very satisfactory results; but the number may be greater or less,as desired. Disk F, which is afiixed to diaphragm D, is of insulating material and has placed in suitable holes therein small tubes G, of carbon, the bore G of which is directly opposite the sockets in the opposite disk and of the same size. A hole is made in the diaph ragm a little larger than the end of the tube, so that each tube will be insulated from the diaphragm. Each of these tubes is electrically connected by a wire H, preferably of No. 40

copper, with one pole of a battery I, there being as many batteries as there are tubes. The other pole of each battery is connected toa wire H, which is wound upon the pole of induction-coil J and forms a primary winding thereon. The ends of these wires are connected to return-wire H, which is electrically connected with diaphragm C. In connecting wire H to tube G the rear end of the bore is closed by a plug a, leaving a socket of about the same depth as the socket in the opposing disk. In each of these sockets is placed a small piece of platinum wire K, which is long enough to pass into the socket of the opposing disk and to be in contact with disk E and tube G when the diaphragms are at their point of farthest separation. Normally the disks are about onequarter of an inch apart. The secondary of the induction-coil is connected with telephonereceiverL. If desired, the secondary winding may be omitted and the pole on which wires H are wound used directly to actuate the diaphragm of the receiver. circuits are electrically independent of each other and so wound and arranged that they act simultaneously in the same way, thereby greatly intensifying the sound emitted by the receiver. In the mast-circuit V represents the coherer or other wave-detector. I have found in practice that very good results are attained by using one vibrating diaphragm with a suitable arrangement of the parts, and I do not confine myself to the use of two vibrating diaphragms, although better results are obtained by the use of two diaphragms.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is'

1. In an electrically-operated sound-receiving apparatus means to intensify the sound comprising a plurality of separated microphone-contacts insulated from each other on These microphonic one side and all being adapted to be actuated by the vibration of a single telephone-diaphragm.

2. In an electrically-operated sound-receiving apparatus means to intensify the ,sound comprising a plurality of independent microphonic circuits adapted to actuate a common magnetic field at the same time in the same direction.

3. In an electrically-operated sound-receiving apparatus means to intensify the sound comprising an induction-coil having a plurality of primary coils connected in independent microphone-circuits, said coils being Wound in the same direction.

4. In an electrically-operated sound-receiving apparatus a plurality of independent microphonic circuits adapted to be actuated by a common means and to actuate a common field at the same time.

5. In an electrically-operated sound-receiving apparatus means to intensify sound, comprising oppositely disposed telephone receiver diaphragms having afiixed to the opposing surfaces of each a disk; one of said disks being of conducting material and the other of nonconducting material; a plurality of opposed sockets in the opposing surfaces of said disks, the sockets of the non-conducting disk having a lining of conducting material, each of said linings being connected to a battery; a wire connecting each of said batteries With a primary Winding of an ind uction-coil; an induction-coil having the secondary Winding electrically connected with a telephone-receiver; a telephonereceiver and means to actuate the oppositelydisposed diaphragms.

In Witness that I claim the foregoing I have hereunto subscribed my name this 19th day of November, 1902.

GUSTAF T. SVVENSON.

Witnesses:

G. E. HARPHAH, M. C. NIoKELEsoN. 

